Star Fungus in suburban garden

I've heard that Star Fungus has been known to cause leaf and twig blight on certain hosts - I have a very large cherry tree and a cedar tree at the base of which I have found what I think is Star Fungus - both trees are showing distress which has so far dumbfounded a couple of experts. Could the Star Fungus be the problem? I'd be really grateful to hear if anyone has any information about this